TY - CONF A1 - Liehr, Sascha A1 - Krebber, Katerina T1 - Applications and prospects for distributed sensing using polymer optical fibres N2 - One of the unique advantages of polymer optical fibres (POF) is that they can be used to measure very high strain values up to 100 % and beyond exceeding the strain limits of silica fibre-based sensor principles. In this paper the distributed strain measurement capabilities of POF based on backscatter change evaluation are summarized and distributed backscatter measurement technologies are intro-duced. Application examples in the structural health monitoring (SHM) field are presented: a promising approach is the integration into technical textiles for high-strain measurement in earthwork structures and crack detection in buildings. The potential of POF for future applications in SHM such as distributed relative humidity sensing is discussed. T2 - International Conference on Smart Infrastructure and Construction CY - Cambridge, UK DA - 27.06.2016 KW - Strain measurement KW - Structural health monitoring KW - OTDR KW - Polymer Optical Fibre KW - Distributed sensing PY - 2016 UR - http://www.icevirtuallibrary.com/doi/abs/10.1680/tfitsi.61279.093 SN - 978-0-7277-6127-9 U6 - https://doi.org/10.1680/tfi tsi.61279.093 SP - 93 EP - 98 PB - ICE Publishing CY - London, UK AN - OPUS4-37230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lenke, Philipp A1 - Wendt, Mario A1 - Liehr, Sascha A1 - Krebber, Katerina ED - Santos, J.L. ED - Culshaw, B. ED - López-Higuera, J.M. ED - MacPherson, W.N. T1 - Distributed humidity sensing based on Rayleigh scattering in polymer optical fibers N2 - In this document a new distributed sensor based on Rayleigh scattering in polymer optical fibers (POF) is proposed and first measurement results of the proposed sensor are shown. Different from Silica glas optical fibers POF absorb high quantities of water resulting in a change of their molecular structure and thereby reducing the present small scattering centers in areas of high humidity. The interdependence between scattering intensity and relative humidity is being investigated in case of steady cycles as well as stepwise changes of humidity and in the presence of moisture. A quantitative measure of humidity and scattering is presented. T2 - 4th European workshop on optical fibre sensors CY - Porto, Portugal DA - 2010-09-08 KW - POF KW - Distributed sensing KW - Rayleigh KW - Scattering KW - OTDR KW - Humidity PY - 2010 SN - 978-0-8194-8083-5 U6 - https://doi.org/10.1117/12.866279 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE IS - 7653 SP - 76533X-1 - 76533X-4 PB - SPIE, the International Society for Optical Engineering CY - Bellingham, Wash. AN - OPUS4-22686 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liehr, Sascha A1 - Wendt, Mario A1 - Krebber, Katerina ED - Jones, J. ED - Culshaw, B. ED - Ecke, W. ED - López-Higuera, J.M. ED - Willsch, R. T1 - Distributed perfluorinated POF strain sensor using OTDR and OFDR techniques T2 - 20th International conference on optical fibre sensors (Proceedings of SPIE) CY - Edinburgh, Scotland, UK DA - 2009-10-05 KW - Distributed strain sensor KW - Optical fiber sensor KW - Polymer optical fiber KW - POF sensor KW - Structural health monitoring KW - OTDR KW - OFDR PY - 2009 SN - 978-0-8194-7814-6 SN - 0277-786X SP - 75036G-1 - 75036G-4 PB - SPIE, the International Society for Optical Engineering AN - OPUS4-20289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Liehr, Sascha A1 - Lenke, Philipp A1 - Wendt, Mario A1 - Krebber, Katerina A1 - Glötzl, R. A1 - Schneider-Glötzl, J. A1 - Gabino, L. A1 - Krywult, L. ED - Bernadette Havranek, ED - Masoud Motavalli, ED - Urs Meier, T1 - Distributed polymer optical fiber sensors in geotextiles for monitoring of earthwork structures T2 - 4th International conference on structural health monitoring of intelligent infrastructure CY - Zurich, Switzerland DA - 2009-07-22 KW - Distributed sensor KW - Optical fiber sensor KW - Geotextile KW - Technical textile KW - POF sensor KW - Structural health monitoring KW - SHM KW - OTDR KW - Fiber optic sensors KW - Polymer optical fibers (POF) KW - Strain sensor PY - 2009 SN - 978-3-905594-52-2 IS - Paper 520 SP - 1 EP - 7(?) CY - Zurich, Switzerland AN - OPUS4-19787 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Liehr, Sascha A1 - Wendt, Mario A1 - Krebber, Katerina A1 - Münich, J.C. A1 - Stempniewski, L. A1 - Metschies, H. ED - Bernadette Havranek, ED - Masoud Motavalli, ED - Urs Meier, T1 - Distributed polymer optical fiber sensors integrated in technical textiles for monitoring of masonry structures T2 - 4th International conference on structural health monitoring of intelligent infrastructure CY - Zurich, Switzerland DA - 2009-07-22 KW - Structural health monitoring KW - Fiber optic sensors KW - OTDR KW - Polymer optical fibers (POF) KW - POF sensors KW - Distributed sensor KW - Strain sensor KW - Technical textiles KW - Masonry PY - 2009 SN - 978-3-905594-52-2 IS - Paper 521 SP - 1 EP - 7(?) CY - Zurich, Switzerland AN - OPUS4-19788 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liehr, Sascha A1 - Wendt, Mario A1 - Krebber, Katerina T1 - Distributed strain measurement in perfluorinated polymer optical fibres using optical frequency domain reflectometry N2 - We present the latest advances in distributed strain measurement in perfluorinated polymer optical fibres (POFs) using backscatter techniques. Compared to previously introduced poly(methyl methacrylate) POFs, the measurement length can be extended to more than 500 m at improved spatial resolution of a few centimetres. It is shown that strain in a perfluorinated POF can be measured up to 100%. In parallel to these investigations, the incoherent optical frequency domain reflectometry (OFDR) technique is introduced to detect strained fibre sections and to measure distributed length change along the fibre with sub-millimetre resolution by applying a cross-correlation algorithm to the backscatter signal. The overall superior performance of the OFDR technique compared to the optical time domain reflectometry in terms of accuracy, dynamic range, spatial resolution and measurement speed is presented. The proposed sensor system is a promising technique for use in structural health monitoring applications where the precise detection of high strain is required. KW - Distributed strain sensor KW - Optical fibre sensor KW - Polymer optical fibre KW - POF sensor KW - Structural health monitoring KW - OTDR KW - OFDR PY - 2010 U6 - https://doi.org/10.1088/0957-0233/21/9/094023 SN - 0957-0233 SN - 1361-6501 VL - 21 IS - 9 SP - 094023-1 - 094023-6 PB - IOP Publ. Ltd. CY - Bristol AN - OPUS4-22379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Liehr, Sascha A1 - Lenke, Philipp A1 - Krebber, Katerina A1 - Seeger, M. A1 - Thiele, E. A1 - Metschies, H. A1 - Gebreselassie, B. A1 - Münich, J.C. A1 - Stempniewski, L. ED - Francis Berghmans, ED - Mignani, Anna Grazia ED - Cutolo, Antonello ED - Patrick P. Meyrueis, ED - Thomas P. Pearsall, T1 - Distributed strain measurement with polymer optical fibers integrated into multifunctional geotextiles N2 - Fiber optic sensors based on polymer optical fibers (POF) have the advantage of being very elastic and robust at the same time. Unlike silica fibers, standard PMMA POF fibers can be strained to more than 40% while fully maintaining their light guiding properties. We investigated POF as a distributed strain sensor by analysing the backscatter increase at the strained section using the optical time domain reflectometry (OTDR) technique. This sensing ability together with its high robustness and break-down strain makes POF well-suited for integration into technical textiles for structural health monitoring purposes. Within the European research project POLYTECT (Polyfunctional textiles against natural hazards) technical textiles with integrated POF sensors, among others sensors are being developed for online structural health monitoring of geotechnical structures. Mechanical deformation in slopes, dams, dikes, embankments and retrofitted masonry structures is to be detected before critical damage occurs. In this paper we present the POF strain sensor properties, reactions to disturbing influences as temperature and bends as well as the results of the different model tests we conducted within POLYTECT. We further show the potential of perfluorinated graded-index POF for distributed strain sensing with increased spatial resolution and measurement lengths. T2 - Optical Sensors 2008 CY - Strasbourg, France DA - 2008-04-07 KW - Fiber optic sensors KW - OTDR KW - Polymer optical fibers (POF) KW - POF sensors KW - Distributed sensor KW - Strain sensor KW - Geotextiles KW - Structural health monitoring PY - 2008 SN - 978-0-8194-7201-4 U6 - https://doi.org/10.1117/12.780508 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 7003 IS - 7003 SP - 700302-1 - 700302-15 PB - SPIE CY - Bellingham AN - OPUS4-17951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liehr, Sascha A1 - Burgmeier, J. A1 - Krebber, Katerina A1 - Schade, W. ED - Liao, Y. ED - Jin, W. ED - Sampson, D.D. ED - Yamauchi, R. ED - Chung, Y. ED - Nakamura, K. ED - Rao, Y. T1 - Fiber optic bend and temperature sensing in femtosecond laser-structured POF N2 - We propose focused femtosecond laser irradiation to create stable and permanent scattering damage in large-core polymer optical fibers. Possible sensing applications using optical time domain reflectometry are discussed and presented. Experiments show that quasi-distributed fiber bend sensors and absolute temperature sensors can be realized by evaluating backscatter intensities. T2 - OFS2012 - 22nd International conference on optical fiber sensors CY - Beijing, China DA - 2012-10-15 KW - Polymer optical fiber KW - POF KW - Optical fiber sensors KW - Bend sensor KW - Temperature sensor KW - Femtosecond laser KW - OTDR KW - Reflectometry PY - 2012 U6 - https://doi.org/10.1117/12.976051 SN - 0277-786X SN - 1996-756X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE IS - 8421 SP - 84213I-1 - 84213I-4 PB - SPIE, the International Society for Optical Engineering CY - Bellingham, Wash. AN - OPUS4-27221 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liehr, Sascha A1 - Nöther, N. A1 - Steffen, Milan A1 - Gili, O. A1 - Krebber, Katerina ED - López-Higuera, J.M. ED - Jones, J. ED - López-Amo, M. ED - Santos, J.L. T1 - Performance of digital incoherent OFDR and prospects for optical fiber sensing applications N2 - We propose a digital implementation of the incoherent optical frequency domain reflectometry (I-OFDR) technique for precise backscatter measurement and optical fiber sensing applications. Specific performance parameters of the I-OFDR are discussed and compared to an analog vector network analyzer-based I-OFDR system. Improved sensitivity, dynamic range and signal stability of the digital I-OFDR is presented and demonstrated by means of quasi-distributed length change measurement. T2 - OFS2014 - 23rd International conference on optical fibre sensors CY - Santander, Spain DA - 02.06.2014 KW - Optical fiber sensors KW - Backscatter measurement KW - Strain sensor KW - OFDR KW - OTDR PY - 2014 U6 - https://doi.org/10.1117/12.2059639 SN - 0277-786X SN - 1996-756X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 9157 SP - 915737-1 EP - 915737-4 AN - OPUS4-30899 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Liehr, Sascha A1 - Lenke, Philipp A1 - Wendt, Mario A1 - Krebber, Katerina ED - Fu-Kuo Chang, T1 - POF sensors integrated in technical textiles for monitoring of earthwork structures and masonry T2 - Structural health monitoring 2009 - 7th International workshop on structural health monitoring CY - Stanford, CA, USA DA - 2009-09-09 KW - Distributed strain sensor KW - Optical fiber sensor KW - Geotextile KW - Technical textiles KW - POF sensor KW - Structural health monitoring KW - SHM KW - OTDR PY - 2009 SN - 978-1-60595-007-5 VL - 2 SP - 1739 EP - 1746 PB - DEStech Publications, Inc. AN - OPUS4-19960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liehr, Sascha A1 - Burgmeier, J. A1 - Krebber, Katerina T1 - Quasi-distributed fiber bend and temperature measurement in femtosecond laser-structured POF N2 - We propose to use focused femtosecond laser pulses to inscribe Scattering damage in the core of polymer optical fibers for interrogation as quasi-distributed sensor points by optical time domain reflectometry. Fiber bend measurement is demonstrated on off-center inscribed sensor points and absolute temperature measurement is presented by evaluation of the constant backscatter intensities from the inscribed structures relative to temperature-dependent Rayleigh Scattering. Application possibilities and limitations of this new approach are discussed. T2 - POF 2013 - 22nd International conference on plastic optical fibers CY - Búzios, Rio de Janeiro, Brazil DA - 11.09.2013 KW - POF KW - Polymer optical fiber KW - Femtosecond laser KW - Optical fiber sensors KW - OTDR KW - Backscatter measurement PY - 2013 SP - 279 EP - 284 CY - Rio de Janeiro, Brazil AN - OPUS4-30082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lenke, Philipp A1 - Wendt, Mario A1 - Liehr, Sascha A1 - Krebber, Katerina T1 - The impact of temperature and humidity on the backscatter profile of PMMA POF N2 - In this paper the influence of combined temperature and strain changes as well as changes of moisture content on polymer optical fibers made of polymethyl methacrylat (PMMA) is investigated. The increase of the scattering coefficient with increasing temperature for various strain levels is observed and quantified. The measurement results of influence of humidity on scattering intensity of PMMA-POF encourage to porpose these as a distributed humidity sensor. T2 - POF 2010 - 19th International conference on plastic optical fibers CY - Yokohama, Japan DA - 2010-10-19 KW - POF distributed sensing Rayleigh KW - Humiditiy KW - OTDR KW - Strain PY - 2010 SP - 1 EP - 7(?) AN - OPUS4-22685 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liehr, Sascha A1 - Muanenda, Y. A1 - Münzenberger, Sven A1 - Krebber, Katerina T1 - Wavelength-modulated C-OTDR techniques for distributed dynamic measurement N2 - We present two wavelength-modulated coherent optical time domain reflectometry techniques for dynamic, quantitative and distributed measurement. The robust and simple techniques are based on backscattering correlations along the time axis and along the pulse wavelength shift axis. T2 - 26th International Conference on Optical Fibre Sensors OFS-26 CY - Lausanne, Switzerland DA - 24.09.2018 KW - Fiber optics sensors KW - Optical time domain reflectometry KW - OTDR KW - DAS KW - Distributed strain sensor KW - Rayleigh scattering PY - 2018 U6 - https://doi.org/10.1364/OFS.2018.TuE15 SP - 1 EP - 4 AN - OPUS4-46414 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -